Me 



U. S. DEPARTMENT OE AGRICULTURE. 
BUREAU OF PLANT INDUSTRY— BULLETIN NO. 57. 

B. T. GALLOWAY, Chiif of Bureau. 



METHODS USED 



CONTROLLING AND RECLAIMING 
SAND DLNES. 



A. S. HITCHCOCK, 
Assistant AGKOSTOLOtiiST, in Chakgk of Cooperative 

EXPEKIMENTS. 



C ^ASR AND FORAC-.E PLANT INVF.RTIGATIONS. 



Issi KJ) ]\r.\i;<.ii 10, U)04. 




WASHINGTON: 

GOVERNMENT PRINTING OFFICE. 

1004. 

Hdrwgrapb 




Glass ^ ^% 



Book. 



W^— 



7^ 

/3r 2-^ 






jl. 57, Bureau of Plant Industry, U. S. Dept, of Agriculture. 



Plate I. 




Beach Grass (Ammophila arenaria Link). 



U. S. DEPARTMENT OF AGRICULTURE. 

BUREAU OF PLANT INDUSTRY— BULLETIN NO. 57. 



B. T. GALLOWAY, Chief of Bureau. 



METHODS USED 



CONTROLLING AND RECLAIMING 
SAND DUNES. 



A. S. HITCHCOCK, 

Assistant Agrostologist, in Charge of Cooperative 
Experiments. 



GRASS AND FORAGE PLANT INVESTIGATIONS. 



Issued Makcii 10, 1904. 




WASHINGTON: • ' : 
government printing office. 
19 04. 



&4 



BUREAU OF PLANT INDUSTRY. 

Beverly T. Galloway, Cliii'f of Bureau. 

GRASS AND FORAGE PLANT INVESTIGATIONS. 

Scientific Staff. 
W. J. Spillman, Agroslologlst. 

A. S. Hitchcock, Assistant Agroslologlst, in Charge of Cooperative Experiments. 
C. V. Piper, Systematic Agrostologist, in CJiarge of Herbarium. 
C. R. Ball, Assistant Agrostologist, in Charge of Work on Arlington Fitrm. 
David Griffiths, Assistant Agrostologist, in Charge of Range Investigations. 



JAN 8 1907 
D.ofO. 



LETTER OF TRANSMITTAL 



U. S. Department of Agriculture, 

Bureau of Plant Industry, 

Office of the Chief, 

Washington ^ D. C.^ January 7, 190 J^. 
Sir: I have the honor to transmit herewith a paper on "Methods 
Used for Controlling and Reclaiming- Sand Dunes," and respectfulh^ 
recommend that it be published as Bulletin No. 57 of the series of this 
Bureau. 

This paper was prepared by Mr. A. S. Hitchcock, Assistant AgTOS- 
tologist, in Charge of Cooperative Experiments, Grass and Forage 
Plant Investigations, and has been submitted b}- the Agrostologist 
with a view to publication. 
Respectfullj', 

B. T. Galloway, 

Ch ief of Bureau. 
Hon. James Wilson, 

Secretary of Agriculture. 



PREFACE 



On the Atlantic and Pacific coasts,. on the shores of the Great Lakes, 
and at numerous places inland, there are areas of sandy land, for the 
most part originally covered by vegetation, but now denuded of plant 
growth through the shortsighted policy which has so often prevailed in 
this country of utilizing everything in sight without reference to the 
future. The Department of Agriculture is frequently called upon for 
advice concerning the proper methods of controlling this sand and pre- 
venting it from drifting. In some cases cultivated fields have been 
invaded and railroad tracks covered. The sand has even invaded 
cities, covering up houses and filling the streets, and much valuable 
property has thus been destroyed. 

Much work has been done in controlling shifting sand dunes in 
Europe during the past century, and methods have been developed 
whereby it is possible to control the sand and in many cases to cover it 
again with vegetation. On account of the importance of the subject. 
Prof, A. S. Hitchcock, of this oflice, was sent to Europe recently to 
stud}^ the methods there used in this work. In the autumn of 1902 he 
visited the Netherlands, Denmark, German}', and France for this pur- 
pose. An outline of the methods that have been successfully employed 
in those countries is given in this bulletin, together with some other 
information of general interest concerning the subject of sand dunes. 
f • W. J. Spillman, 

Ag7'ostoloffis(. 

Office of the Ageostologist, 

Washington, D. C, Deceiiiber 16, 1903. 

5 



CONTENTS 



Page. 

Introduction 9 

Formation of sand dunes 9 

Action of the wind upon drifting sand 11 

Artificial fixation of dunes 13 

Binding the sand 14 

Binding by means of grasses 14 

Transplanting 14 

Arrangement of the plantation 16 

Formation of the barrier dune 17 

Binding by means of heather 19 

Laying the heather 19 

Binding with sand hedges 20 

Forestation 21 

Fixation as oljserved in Europe 22 

The Netherlands 22 

Coastal dunes 22 

Interior dunes 23 

Denmark 25 

Oxbol 25 

Skagen 26 

Germany 27 

France 29 

Summary 32 

Description of plates 35 

7 



ILLUSTRATIONS. 



PLATES. 

Page. 

Pl.\te I. Beach grass Frontispiece. 

II. Fig. 1. — Dunes held b}- covering of heather. Fig. 2.— Making a road 

in the dunes 36 

III. Fig. 1. — Pine plantation in covering of heather. Fig. 2. — Heather 

among the dunes 36 

IV. Fig. 1.— Beach grass plantation along base of dunes. Fig. 2. — Beach 

grass and sand fence on barrier dune 36 

V. Fig. 1. — Lee slope of barrier dune. Fig. 2. — Remains of once buried 

forest 36 

VI. Fig. 1. — General view of barrier dune. Fig. 2. — Unreclaimed shift- 
ing dune 36 

VII. Fig. 1. — Digging beach grass for planting. Fig. 2. — Transplanting 

beach grass 36 

VIII. Fig. 1. — Sand fences protecting base of dune. Fig. 2. — Protecting a 

road through the dunes 36 

IX. Fig. 1. — Shifting dunes held by brush fences. Fig. 2. — Shifting dunes 

held by reed fences 36 

TEXT FIGURES. 

Fig. 1. Drifting sand as affected by a solid fence 12 

2. Drifting sand as affected by an open, inflexible obstruction 12 

3. Drifting sand as affected by an open, flexible obstruction ^ 12 

4. Spade used for planting beach grass 15 

5. Method used in planting beach grass 16 

6. Diagram showing the successive steps taken in forming a barrier dune. 17 

7. Repairing a small breach in a barrier dune by planting grass 18 

8. Repairing a larger breach by means of sand fences 18 

9. Spade used in Prussia for transplanting young trees 21 



B. P. I.— 92. G. F. P. I.— 102. 

METHODS USED FOR CONTROLLING AND RECLAIM- 
ING SAND DUNES. 



INTRODUCTION. 

The sand-dune areas of Europe are of especial interest because they 
present conditions similar to those found in the United States and 
because it is there that the methods of reclamation were first applied 
and later most successfully developed. 

In order to investigate the methods used and determine to what 
extent they might be applied in this country, the writer visited several 
regions in Europe where the conditions and methods may be considered 
representative — the Netherlands, Denmark, the southwest coast of 
France, and the Kurische Nehrung on the northeast coast of Germany, 
In Prussia much work has been done along the coasts of the Baltic and 
North seas, but this is so well described in Gerhardfs ■' admirable book 
upon the dunes of Germany that other points than the ones mentioned 
were not visited. 

There are other localities of minor importance where dunes occur 
and where efl'orts toward reclamation liave been made, but it was not 
learned that the methods used differed essentially from those investi- 
gated. Lack of time prevented visits to certain other interesting 
interior regions, such as the Banat plain of southern Hungarj^, the 
north shore of the Black Sea, and Russian Turkestan. The last two 
regions are of importance because of the efforts put forth by the rail- 
roads to prevent the enroachment upon their right of waj^ by shifting 
dunes. 

FORMATION OF SAND DUNES. 

Sand hills or dunes usually occur along a sandy seacoast. The sand 
is constantlj^ washed up by the waves and when dry is readily carried 
inland by the wind. On a rocky or marshy coast this does not occur. 

« Paul Gerhardt, Handbuch des deutschen Diinenbaues, Berlin, 1900. This is a very- 
complete and detailed account of the sand dunes of Germany, including geology, flora, 
formation, reclamation, and historical notes, and is the most elaborate work of this 
nature thus far published. The writer is indebted to this work for the text figures 
used in this bulletin. Mr. Gerhardt was superintendent of the Konigsberg district 
(Regierungs und Baurat) and was later advanced to the charge of the entire work at 
Berlin. 

9 



10 METHODS USED FOR CONTROLLING SAND DUNES. 

Under the action of the wind the sand accumulates in ridges or hills of 
irregular contour and extent, depending upon the force and direction 
of the prevailing winds. It is not intended here to go into the details 
of dune formation, a subject which has been elaborated in Gerhardt's 
book and also in numerous lesser works. Suffice it to say that ordi- 
narily a dune passes through a rather definite series of changes. It is 
formed near the beach and travels back toward the interior. A typ- 
ical wandering dune presents a gradual slope toward the wind and an 
abrupt slope on the lee side. The wind forces the sand up the slope 
and it falls over the edge. The hill or ridge then travels in the direc- 
tion of the prevailing wind at a rate depending on the force and con- 
stancy of the latter. Such a hill is called a wandering dune. As the 
dune recedes from the coast a new one may form at the beach. 

Upon the wandering or active dunes the sand is shifting to such an 
extent that vegetation does not establish itself. Consequently such 
dunes are bare. During wet periods seeds may germinate, but sooner 
or later the flying sand destro3^s the plants either by cutting them off 
as by a sand blast or by burjdng or uncovering them. However, as 
the action of the wind becomes less forcible at a distance from the 
strand, vegetation is at last able to become established and resist the 
enfeebled sand blast. A wandering dune is thus gradually converted 
into a lixed dune, which, if left to itself, finally becomes forested. 

Similar dunes are often formed along the larger rivers or on interior 
sandy wastes such as are found in the central portions of the Nether- 
lands and Denmark. It not infrequently happens that a fixed dune 
becomes converted into a wandering dune. This occurs through the 
removal of the vegetation, either by natural means or as the result of 
man's carelessness. The result in the first case is usually brought about 
by changed conditions, such as the direction of the wind, whereby the 
vegetation dies in certain spots and " blowouts " are formed. Such 
cavities or blowouts gradually enlarge as the surrounding vegetation 
is undermined and the result may be the birth of a wandering dune. 
But from an economic standpoint by far the greatest harm has come 
from the removal of forests from fixed dunes. The Kurische Nehrung 
in Prussia and the coast dunes of the Netherlands were at one time 
covered with forest and gave no trouble. Other cases are known 
where dunes held permanently b}^ a covering of grass have been con- 
verted into wandering dunes by the pasturing of cattle upon them, 
thus cutting up the sod. 

Sand dune* of any considerable extent are rarely found along the 
seacoast in warmer regions, because the long growing season is more 
favorable to vegetation. The forest, or at least a scrubby growth of 
shrubs, usually comes down close to the high-water mark. The severe 
winter storms of the high latitudes are chiefly responsible for the great 
dune areas of the north. 



FOEMATION OF DUNES. 11 

In many cases the wandering dunes encroach upon arable land, upon 
forest, upon valuable property such as railroads and buildings, or 
upon rivers, harbors, or other water waj's. This usually indicates 
that there has been a recent change of conditions resulting in the 
formation of active dunes. Seaside resorts upon sand}^ beaches are 
often seriously damaged by the formation of dunes and blowouts upon 
various portions of the property. 

In addition to the trouble arising from the encroachment of sand 
at points Avhere it does damage, it should be understood that there are 
large areas of sandy land consisting of dunes in various stages of fixa- 
tion, interspersed with portions of level and sometimes arable land. 
These level spots represent portions where the wind has swept away 
the sand down to moist soil, which usually has a definite relation to 
the water level. Such areas of dunes may include many square miles 
and are useless for agricultural purposes. It is thus seen that the 
fixation of dunes may be for two purposes — to protect propert}^ in the 
lee or to convert a useless area of waste land into a productive forest. 

ACTION OF THE WIND UPON DRIFTING SAND. 

When the wind sweeps over a free surface of drifting sand it acts 
about equall}^ throughout; but an obstruction of an}^ kind, such as 
a log or a bunch of grass, at once modifies the action of the wind. 
A solid object increases the force of the wind around the sides, and 
hence the sand is excavated. In the lee of the object the sand will 
accunuilate. If two such obstructions are near together a channel is 
formed between them and once formed deepens with astonishing 
rapidity. The carrying power of the wind increases much more 
rapidly than the increase in the velocity." Consequent^, any increase 
in the velocity is immediately noticeable in the increased erosive 
power. The erosive power of the wind is not identical with the 
carrying power, for in the first case the wind overcomes cohesion and 
in the second case it overcomes weight. If the velocity of the wind 
decreases, the sand previously held in suspension is deposited. 

If a solid fence is placed upon the sand at right angles to the wind 

« Theoretically the transporting power of the wind varies as the sixth power of the 
velocity — that is, if the velocity is doubled the carrying power is 64 times as great. 
It is clear that the force exerted by the wind upon a fixed surface increases as the 
square of the velocity, for if the velocity of the wind is doubled there will be twice 
as much air striking the surface with twice the velocity. Furthermore, if the velocity 
remains the same the force exerted increases with the surface — that is, with the square 
of the diameter. The moving power then varies as the product of the square of the 
velocity and the square of the diameter. But the force or work done, which is the 
same as the weight of the object transported, varies with the cube of the diameter; 
or, putting it all in terms of velocity, the force varies as the sixth power of the 
velocity. 



12 



METHODS USED FOR CONTROLLING SAND DUNES. 



the sand is excavated in front (tig. 1). The wind, unable to proceed, 
is divided into currents in all directions. Those going downward 
scoop out the sand, thus forming a drift a short distance in front. 
This increases until its height equals that of the fence, when the w4nd, 
no longer meeting with the obstruction, allows sand to be deposited 




Fig. 1.— Drifting sand as affected by a solid fence. 

in this channel, and it fills up, covering the fence. Similarly at the 
ends of the fence the wind currents are increased and the sand is 
scooped out. If the fence is raised so as to allow a space beneath, the 
sand is rapidly scooped out below. The same result occurs beneath 
buildings, trestles, or other works which allow a space beneath, 




L^tr:^^ 



Fig. 2. — Drifting sand as affected by an open, inflexible obstruction. 

through which the wind rushes with increased force. If. however, 
the obstruction is not solid, but more or less open, as a pile of brush 
or a bunch of grass, the action is entirely difi'erent. The wind passes 
through the obstruction, but with decreased velocity"; hence, sand is 
deposited within the obstruction. No excavation takes place in front 




Fig. 3. — Drifting sand as affected by an open, flexible obstruction. 

or around the sides. If the obstruction is stiff and inflexible like a 
sand fence, the sand is deposited on both sides (tig. 2), the windward 
slope being gradual and the lee slope more abrupt. If the obstruc- 
tion is tlexible like a bunch of grass, most of the sand is deposited in 
the lee (tig. 3). Of course there are all gradations between the two 
classes, and various circumstances may modify the usual action. 

It may be further stated that when the wind is blowing up an 



FIXATION OF DUNES. 13 

incline, the surface velocity increases with the steepness. A small 
object is easily blown uphill. But when the wind l)lows down a slope, 
eddies form which usually produce a current uphill at the surface. 
Thus it happens that while small bodies can be blown uphill easil}^ it 
is not often that they are blown downhill, but must fall from their 
own weight when the slope is steep. The fact that the velocity of the 
wind at the surface on the windward side of a dune increases with the 
slope results in producing- a normal incline, which represents a bal- 
ancing of forces. Usually this incline is quite gradual compared with 
the lee side of the dune, where the slope is the greatest at which the 
sand will remain in place — about 30°. 

Sand can be removed from one place to another farther on b}' placing 
a suitable obstruction above, with a space between it and the surface 
of the sand, which will increase the wind velocity at this point. Sand 
may be tilled in at any point by interposing an open obstruction, such 
as brush or a sand hedge, or by planting grass. The practical appli- 
cation will be referred to farther on. 

ARTIFICIAL FIXATION OF DUNES. 

The fixation is most permanent when the dunes are covered with 
forest; hence, forestation is the ultimate aim wherever possible. But 
there is a narrow strip of territory just back of the strand where 
trees will not grow on account of the exposure to the severe winds 
and the action of the ocean spra}-. The width of this strip depends 
upon local conditions and may vary from one to several rods. The 
force of the wind is influenced by the character of the coast. Expe- 
rience soon demonstrates how near to the strand a forest ma}^ be 
produced. 

When the work of fixation is completed there will be a forest over 
the greater part, but a strip along the coast remains which must be 
permanently held in place by some other method, usualh^ by the plant- 
ing of grass. When the forest is once established it is cared for and 
preserved according to the usual methods of forestry'. Usually it is 
impossible to establish a forest directly upon the sand dunes either by 
sowing the seed or setting out 3'oung trees, because the drifting sand 
cuts the leaves and bark or uncovers or buries the young plants. 
Sowing the seed has been tried several times, but there remain of this 
work only a few" scattered patches of trees in protected places. It is 
therefore necessar}- to hold the sand in place by some kind of a cov^er- 
ing until the trees can obtain a start, when they form a covering 
themselves. 

The work of fixation is thus divided into two rather distinct stages: 
(1) Preliminary; holding the sand in place. (2) Permanent; establish- 
ing a forest. Upon the coast strip the work does not proceed beyond 
the first stage, but the maintenance of the covering in a satisfactory 
condition requires constant care. 



14 METHODS USED FOR CONTROLLING SAND DUNES. 

BINDING THE SAND. 

There are many methods which have been employed at various times, 
but those now in successful use on a large scale may be considered 
under three heads: (1) Transplanting- sand-binding plants upon the 
dunes, sufficiently thick to form a living cover; (2) covering the entire 
surface with some inert material which prevents the wind from reach- 
ing the sand, and (3) covering the surface with a network of brush 
fence which, while not preventing the wind fi om reaching the sand, 
lessens its velocit}^ and prevents drifting. It may be remarked that 
numerous experiments have demonstrated the futilit}' of sowing the 
seeds of any plant directly upon the unprotected surface of the bare 
sand. 

These methods, as the}^ have been finall}^ elaborated, will now be 
described. For the historical development and the description of 
special methods to meet unusual conditions, the reader is referred to 
Gerhardt's book previousl}' mentioned. 

BINDING BY MEANS OF GRASSES. 

Various plants for binding the sand have been tried, but none have 
been found so successful as grasses. Willow cuttings have been 
emplo3'ed in a few cases, but their use has not proved satisfactory. Of 
the grasses the species used almost exclusively is beach grass {A/n- 
mo2)hila arenaria Link), shown in Plate I, frontispiece. A kind of 
wild rye {Elymus arenarius L.) has been used occasionall3^ Beach 
grass grows naturall}^ on the dunes all along the north Atlantic 
coasts of both P^urope and America as far south as Morocco and North 
Carolina. It grows in clumps to the height of one to three feet and 
spreads by means of extensivel}^ creeping underground stems or 
rhizomes. 

An important character of beach grass is that it grows with most 
luxuriance where the sand is drifting. In quiet sand it persists for a 
few 3^ears but gradually dies out. The drifting sand seems to supply 
the conditions for continued rejuvenation of the growth as the sprouts 
force their way up through the accumulating sand. 

Transplanting. — Beach grass may be transplanted in the autumn or 
spring ; in the autumn from the time it is mature, which may be as 
early as September, until the ground freezes, and in the spring from 
the time the ground thaws until growth starts. The grass is usually 
transplanted in the autumn, because at this time the requisite labor is 
more easily obtained, and furthermore it is then easier to pick out the 
individuals that are at the right stage of growth. It is best to choose 
moist or foggy weather, as the plants are more certain to grow, the 
danger of desiccation is less, the sand being damp it is more easily 
manipulated, and the work can be performed much more comfortably^, 



BINDING SAND WITH GRASSES. 



15 



as the fl3'ing sand .seriously interferes with planting during- dry- 
weather. 

The plants chosen for transplanting should be two years old and 
have at the base one or two nodes. The roots spring from these nodes; 
consequently at least one node must be present. More than two are 
not necessary and would be a waste of material, though they do no 
other harm than to interfere with planting in proportion to their num- 
ber. One-^'ear-old plants are not strong enough and have not devel- 
oped the nodes sufficiently for transplanting. Plants more than two 
years old are proportionately lacking in vitality and do not throw out 
roots with sufficient vigor. With some experience laborers are able 
to distinguish at sight plants of the right age. If the grass is grow- 
ing in loose sand and has not l)een covered deeply, it 
may be pulled up by hand. But usualh' it is neces- 
sary to cut the rhizomes below the surface of the 
sand, after which the plants can be easil}" pulled up. 
The method of procedure is for the workman to seize 
a suitable clump of the grass with the left hand and 
with a spade held in the right hand strike into the 
sand in such a manner as to cut otf the rhizomes below 
having one to three nodes at the lower end (PI. VII, 
fig. 1). The bunch is then pulled up and placed in a 
pile or under the left arm. When a bundle has accum- 
ulated, it is tied up and is read}^ for use. The spade 
used is a light tool special!}^ made for the purpose, 
with a sharp edge or point and a short handle. 
Sometimes an ordinary spade, such as is used in dig- 
ging, is put to this service. 

If the grass for transplanting is taken from the 
dunes that are to be fixed, care should be taken not to 
remove too much from one place and allow the wind 
to make a blowout. It should be chosen from places 
where the grass is growing too thickly. The arrange- 
ments should be such that the grass can be planted soon after being 
dug or the roots may dry out too much. For the same I'oason it is 
best to dig the plants near the place where they are to be set out, 
thus reducing the distance of transportation. 

The grass ma}' be set out in various ways, but the method which 
seems to be most satisfactory is as follows: The planting is done by 
two persons working together. One prepares the holes and the other 
inserts the grass. The holes are made with a spade specially con- 
structed, as shown in the illustration (fig. 4). The blade is rather heavy 
and has a sharp edge l)elow. The operator lifts the spade by the cross 
bar or handle with ])oth hands, and allows it to drop into the sand 
mostly by its own weight. He moves the handle back and forth once 
17170— No. 57—01 2 




Fig. 4.— Spade used 
for planting beach 
grass. 



16 METHODS USED FOR CONTROLLINO SAND DUNES. 

or twice, or until the blade has been worked down throuoh the sand 
to the required depth. This makes a V-shaped opening in the sand 8 
to 12 inches deep. The sand must l)e moist enough to retain its posi- 
tion or this method can not be used. The second worker now takes a 
portion of grass sufficient for one planting and places it in the hole, 
flattening out the bunch properl}'. The first worker puts the spade in 
the sand just behind the bunch, pushes the sand up tightly against the 
grass, and the operation is completed (fig. 5). The grass can be set 
out quite rapidly in this manner (PI. VII, fig. 2). 

Arrangement of the 2)lantation. — If the dunes are alread}" partially 
covered with beach grass, it may be necessar}^ to plant only here and 
there in the bare places to prevent excavation by the wind or the 
formation of blowouts. If the sand is bare or covered with onl}^ a 
scattering growth, it is necessar}^ to plant systematical!}' . The most 
common method is to set the plants in rows. In Germany they are 
set in squares, the quadrat system, which will be 
described under methods used in the Kurische 
Nehrung, When the gi'ass is set in rows, the 
))unches are placed so that they alternate in adja- 
cent rows. Ordinaril}^ the rows are fairl}' straight 
and perpendicular to the prevailing direction of 
the wind. In an extended area, where there is a 
succession of dunes and depressiions, the rows ma}^ 
.•■-■■.•;::•;.;•■■-■ follow the contour lines. Rows in the direction 
FIG 5.-Method used in ^^ ^^^^ ^-^^ ^\^oxM be avoided, as a channel will 

planting beach grass. ' 

be formed between. In broken dune areas the 
plantings are made between the dunes and along their slopes, but 
leaving the tops bare (PI. IV, fig. 1). 

Usually there is no preparation of the dunes in the way of leveling 
or filling, as it is found more economical to allow the wind to do this 
work. The idea is to accumulate sand in the channels and hollows and 
allow the wind to blow^ ofl' the tops of the hills. To aid in leveling 
the high places the grass is removed from these so that the wind can 
have free access. No planting may be necessar}^ in the low places 
where the sand has been blown off down to moisture, as such situa- 
tions support considerable vegetation. The planting is begun at the 
base of the slopes and proceeds toward the top, as it is the lower por- 
tions that are eroded the most rapidly-, for the reasons stated when 
discussing wind velocity. 

The thickness of the planting depends upon local conditions. If it 
is necessary to accumulate sand rapidlv, as in filling a channel, the 
grass is planted in large bunches placed closely together; but where 
the sand is easily accumulated, the grass is set thinly to prevent its 
being covered. Under average conditions the rows are 15 to 18 
inches apart and the plants about a foot apart in the row. The amount 




FOKMATION OF BAKKIER DUlsrE. 



17 



of grass in a bunch is about what can be easil}^ taken in the hand and 
may consist of four or five stalks. 

Formation, of the harrier dime. — The grass planting previousl}^ 
described applies particularl}" to the large dune areas near the coast. 




Fuj. 6. — Diagram showing in cross section the successive steps t:iken in forming a barrier rtunc. 

strand is at the left. 



The 



where this process is preparator}- to the planting of trees. The 

function of the grass has been fulfilled when the forest is established. 

As stated in an earlier paragraph, there is a strip of sand along- the 



18 METHODS USED FOR CONTROLLING SAND DUNES. 

coast just back of the strand which presents conditions unfavorable to 
forest growth. Here it is necessary to hold the sand in place perma- 
nently by means of the grass. To do this requires constant super- 
vision. Through various causes bare spaces are likelj^ to occur which 
must be replanted to prevent the formation of blowouts. Sometimes 
the bunches must be thinned, as the presence of two large adjacent 
bunches ma}^ cause the wind to draw through between them and form 
a channel. 




.Strand ^- -f-.-f -^'.'^ i JfcaM-^JM^ 

Fig. 7. — Rc'ijairiiig a small breach in a barrier chine by planting grass. 

On the Kurische Nehrung in Prussia and along the southwest coast 
of France it has })een found advisable to form an artificial protecting 
dune extending all along the sea in front of the forest (PI. VI, fig. 1). 
This dune is produced b}^ accumulating the sand rapidly so as to form 
a long ridge (fig. 0). For this purpose brush fences, which consist of 
rows of brush or rough branches driven into the sand firmly but rising 
above the surface about 30 inches, are used. The tops should he on a 
level. Two such rows are placed about 6 feet apart. These fences 
allow the wind to pass through, but reduce its velocity, and hence sand 
is deposited within and on both sides. When the sand has reached the 
top of the fences, a second pair is placed above. When a ridge has 
been formed, beach grass is planted in rows parallel to the crest. At 
first, plantings are made along the slopes and a short distance in front 
toward the strand. As the sand accumulates, the grass is planted far- 
ther to the windward. Finally the protecting dune assumes a com- 
paratively permanent form, with a long slope to windward (toward 



Fk; 8. — Repairing a larger l)reaeh b> means of sand fences. The diagram represents a cross .section 
of a dune with two rows of sand fence parallel to the dune and cross rows extending from the 
outer row to the broken face. 

the sea) of 4 to 5 degrees, or about 1:9, and a steep slope on the lee 
side of about 1:2 (PI. V, fig. 1). As a matter of fact, the windward 
slope is often much steeper — as much as 1:6 or even 1:4. 

In practice this protecting dune must be established upon an area 
more or less broken by dunes of irregular shape. The ground line 
for the ridge is laid out to follow the coast in a general way, but to 
avoid all sharp bends or indentations of the shore line. The hollows 
and channels are filled up to the desired height, while the peaks and 
any small dunes lying in front are denuded of grass so that they are 



BINDING SAND WITH HEATHER. 19 

ultimatel}' removed by the wind. Such a ridge protects the forest or 
arable land lying- in the lee, but requires constant supervision to keep 
it in repair. The danger is from encroachment of the sea during 
storms, especially in winter. A single severe storm may break 
through and destroj^ several rods of well-built dune. Such a breach 
must be repaired as soon as possible, or the wind will still further 
erode the unprotected sand and enlarge the opening. These l)reaks 
are best filled in by means of sand fences (tigs. 7 and 8 and PI. IV, 
fig. 2). 

It may be mentioned here that reclamation of sand dunes on a large 
scale is carried on in Europe b}" the general governments, as private 
individuals lack the necessary unity of purpose. This will be touched 
upon under the head of the particular regions visited. 

BINDING BY MEANS OF HEATHER. 

As stated previously, it is necessary to hold the sand in place while 
a forest is being established. Near the seacoast this is usually done by 
planting the beach grass, which is found growing wild upon the dunes. 
There are, however, vast stretches of inland dunes where beach grass 
does not grow, and the cost of transportation renders this method less 
economical than others. When fixing the sand is but preliminar}" to 
planting trees the method used depends upon the relative cost. Along 
the coast, where the fixation is permanent, the planting of beach grass 
is the only method which meets the requirements, and hence it is used 
even when it becomes necessary to import the plants. 

For a temporary covering any cheap inert material which meets the 
condition, such as brush, straw, or sawdust, may be used, but by far 
the most satisfactory material in northern Europe is the heather ( Cal- 
luiia vulgaris Salisb.). As it is a common plant in the sand-dune 
regions this method is used in the central portion of the Netherlands 
and in the interior regions of Denmark (PI. Ill, fig. 2). The heather 
can be used also in areas near the seacoast, as in western Denmark. 

Laying the heatJier. — The heather is cut off with scythes, spread 
over the surface, and held in place by a little sand. The scythe used 
for mowing is short and somewhat resembles American l)rush scythes. 
The heather is then tied in bundles and carried to the place where it 
is to be used. Sometimes it may be necessary to transport the bundles 
some distance, as the heather grows usually only in the low places 
between the dunes, or at least it is here that it grows in sufficient 
luxuriance to be cut profitably. Since the heather is not planted, it is 
not necessary to use it immediately after gathering, as in the case of 
the grass. The plants are spread out ffat upon the surface, overlap- 
ping each other in the rows, and are held in place b}^ being partially 
covered with sand.- The surface is not prepared, except that small 
inequalities are leveled so that the wind can not get beneath the layers 
of heather (PI. II, fig. 1). 



20 METHODS USED FOR CONTROLLING SAND DUNES. 

The heather is also used in road making. The roads through the 
dunes are laid out and graded in the usual manner, after which heather 
is laid thickl}^ in courses upon the surface, thus preventing the wheels 
of vehicles from sinking into the sand (PI. II, tig. 2). 

BINDING WITH SAND HEDGES. 

Sand hedges are used for binding when other methods are not prac- 
ticable, or where the sand is drifting with especial force, or where it 
is desired to accumulate sand with rapidit3^ In general this method 
involves the use of some inert material, like brush or rows of stakes or 
reeds, which projects above the surface of the sand and reduces the 
velocit}^ of the wind without causing deflecting currents, which erode 
the sand. The entire surface of the sand is not covered, but the action 
of the wind is hindered sufiicientl}^ so that the sand present remains in 
place and additions from the strand or from neighboring unprotected 
areas are accunudated (PL IX, figs. 1 and 2). 

The sand fences or hedges are made from brush obtained in the 
forest. The branches are cut into pieces from 18 inches to 2 feet long, 
with sharp ends. The ends are sharpened by the slanting stroke which 
severs the stick. The side twigs are cut off roughly. These stakes 
are driven into the ground in rows, or, still better, in squares, thus 
catching the sand from all directions. The stakes project above the 
surface about a foot and should be on a line at the top, parallel with 
the general plane of the dune surface. The size of the squares depends 
on the tendency to drift, and varies from 9 to 12 feet. The rows 
should be at right angles to the direction of the prevailing wind. On 
dunes near the shore the rows should run parallel to this, with the 
short rows perpendicular. In covering a surface the long rows are 
first placed and the squares made by inserting crossrows between. 
The stakes should be close enough together in the rows so that the 
average width of the space is about equal to the average diameter of 
the stakes. The size of the stakes varies from half an inch to 2 inches 
(PI. IX, fig. 1). 

The common reed of Europe is utilized in the same manner. It is 
cut into the proper lengths and the pieces are set out in rows by about 
the same methods used in grass planting (PI. IX, fig. 2). 

As previously stated, sand fences are used to repair breaks in protect- 
ing dunes, to fill channels previous to planting grass, or wherever it is 
necessary to accumulate sand. In these cases it may be advantageous 
to have the fences higher than when they are intended primarily to 
bind the sand. Sand fences are sometimes used along the base of dunes 
near the strand, where grass will not grow on account of occasional 
high tides (PI. VIII, fig. 1). 

In place of sand fences heather or brush placed in rows or squares 
and held in place by a little sand thrown over one edge is sometimes 
used. 



ES'IABLISHING A FOREST. 



21 



FORESTATION. 

The processes previousl}^ described are as a rule only preparatory to 
establishing- a forest. When the dunes are covered with trees the}' are 
permanently fixed, and the trees being cared for according to the usual 
regulations pertaining to forest management become a source of revenue 
to the Government. It appears that most of the large and troublesome 
dune areas along the coast were at one time covered with forest, not- 
ably Holland and the Kurische Nehrung, but 
through lack of foresight these areas were de- 
nuded of forest and ere long were converted into 
wastes of drifting sand. Some attempts were 
made in the early part of the last century to re- 
forest these areas b}' sowing the seed of forest 
trees. These trials all resulted in failure, 
although there are here and there in protected 
situations small and stunted groves which sur- 
vived. It has l)een proved that the only satisfac- 
tory method of establishing a forest in the north- 
ern dune areas is by setting out 3'oung trees, after 
the sand has been fixed b}^ one of the methods 
described in previous paragraphs. In Gascony 
on the southwest coast of France, however, the 
forest has been successfully established from seed 
under conditions which will be described when 
speaking of the methods used in that countr}". 

The trees used are mostly conifers, the species 
depending upon the locality. In the Netherlands 
Pin us ((ustrtaca and P. hiricio are most successful 
on the coast and P. sylve-stris on the interior dunes; 
in Denmark Plnu.s mont<ma on the coast and 
Picea exceha (preceded by Pinus montcma) on the interior ''heide;" 
Plnus sylvestris and P. montana on the Kurische Nehrung; and Phnis 
maritlma in Gascony. Deciduous trees, such as birches, alders, and 
oaks, are vised along the roads and serve as fire guards. 

The seedlings are raised in nurseries located at convenient points 
near the area to be planted. These nurseries are often surrounded by 
wire netting to keep out rabbits and other harmful animals, and may 
also be protected from the wind by wind-breaks of reeds or cut 
branches of pine. 

The 3'oung trees are transplanted when one or two years old (fig. 9). 
The growth is bften quite slow at first and the young forest needs 
much attention. Some of the trees die and these must be replaced. 
But on the whole these operations have been very successful, and now 
there are several areas of forest that are producing an income to the 
Government. 




Pig. 9.— Spade used in Prus- 
sia for transplautiag- young 
trees. 



22 METHODS USED FOR CONTROLLING SAND DtJNES. 

FIXATION AS OBSERVED IN EUROPE. 

For the purpose of observing the details of the European processes 
of dune reclamation as actually practiced, the Netherlands, Denmark, 
German}^, and France were visited. Below are given the details of the 
methods used in the countries mentioned, which may be taken as fairly 
typical of the work throughout Europe. 

THE NETHERLANDS. 

Through the kindness of the American minister at The Hague, Mr. 
Newel, and Mr. Van Marez Oijens, the minister of the department 
of waterworks, a detailed examination of the dunes near Alkmaar and 
in the vicinity of Barneveld was made. 

COASTAL DUNES. 

A line of dunes extends all along the coast of the provinces of North 
Holland and South Holland. These are two of the richest provinces 
in the Kingdom, and it becomes of great importance to prevent the 
encroachment upon the agricultural lands which lie just back of the 
coast. The dunes were visited in company with Mr. Van Dissel, who 
has charge of this portion of the work, and who explained the details 
of the methods used at that point. The particular portion of the dunes 
visited was near the little town of Schoorl. The land to be reclaimed 
was the property of the General Government. At an earlier period 
this region was covered with forest trees, but these were cut off to be 
used for fuel and other purposes. The result was disastrous. The 
covering of vegetation was broken through, allowing the wind access 
to the sand, and tinall}^ the w^hole area was converted into a series of 
shifting dunes. About forty j^ears ago an attempt was made to reforest 
these dunes by sowing the seed of pines. These seeds seem to have 
germinated quite readily, but the seedlings were unable to withstand 
the severe conditions, and now all that remain to show for the work are 
a few isolated groves in protected places. The Government has now 
planned an extensive system of reclamation which in time will convert 
all of this waste into a productive forest. 

The preliminary fixation is done by planting beach grass, as indi- 
cated in a previous paragraph. (See PI. VII, fig. 1.) In this region 
there is no inert covering that can be economically used, but beach 
grass grows abundantlj^ all along the coast. As it is easier to obtain 
the necessary labor in the autumn, the planting takes place at this 
season rather than the spring. Furthermore, it is easier in the autumn 
for unskilled laborers to choose grass of the proper age for planting, 
as in the spring the portion above ground is dried and brown, thus 
making it difficult to distinguish between the shoots of diti'erent 
ages. Care is taken to gather grass for planting from places where 
it is growing thickly, so as not to rob the sand of its covering to an 



FIXATION IN THE NETHERLANDS. 23 

injurious extent. In gathering the grass a short- handled spade is used. 
The little bunches are tied in bundles of 72, this ])eing a convenient 
armful and also a convenient number for calculation, six dozen. The 
planting is done by two persons working together, as already described. 
Sometimes the sand is pressed back upon the transplanted grass by 
means of the foot instead of the first worker using the spade. While 
a handful is more than necessary, experience has shown that some of 
the grass fails to grow. Even though it does not grow, the dead grass 
acts as a barrier to the sand for some time, at least one year. The 
grass is planted in rows about 40 centimeters (16 inches) apart and 
30 centimeters apart in the row, the bunches in successive rows 
alternating. If the sand is not entirely bare, the bunches are planted 
here and there where the}' are needed, Ordinaril}' no attempt is made 
to level or alter the ground and in man}' places steep hillsides are 
planted. However, there are cases where the land is somewhat pre- 
pared, especially by leveling sharp points that rise above the general 
surface. In the region visited there is no protecting dune along- the 
strand, and such a method of protection seems not to have been used 
in Holland. 

After the sand has been planted to grass to prevent its drifting, the 
trees are set out. The young trees are grown in nurseries from seed 
planted usually in April. Trees are set out when one or two years old 
in spring or fall, according to conditions. Several species have been 
tried, such as Ahles haUamea^xM.^ Pmiis austriaca Link, P, larlcio 
Poir., P. marithna Lam., P. rigida Mill., P. si/lvestris L., Quercus 
pediineuhita Ehrh., Q. ruhra L., and Rohinia pseudacacia L. 

It has been found that the species best adapted for exposed situa- 
tions are Pinus austriaca and P. laricio. Some other pines, especially 
P. ■'^i/lrestris, are good for the more sheltered places. 

The cost of setting the grass is 50 to 75 guilders'^* per hectare, and 
the total cost of reforesting is about 150 guilders per hectare (about 
$22 per acre). It must be remembered, however, that labor, the most 
important item of expense, costs much less than in the United States. 

INTERIOR DUNES. 

In company with Mr. Jager-Gerlings, an interior dune area in the 
Province of Gelderland, east of the town of Barneveld, was next vis- 
ited. This is known as heath land because heath or heather {Calhina 
mdgaris) is al)undant here. The Government has purchased a quan- 
tity of this waste land and proposes to convert it into forest. The 
land is sterile and the country almost uninhabited. 

Here the preliminary fixation is by means of covering the sand with 
layers of cut heather. The heather is cut with a short, thick scythe 

« A guilder, gulden, or florin is worth about 40 cents in American money. A hec- 
tare ia equal to 2.471 acres. 



24 METHODS TTSED FOR CONTEOLLING SAND DUNES. 

with a straight handle, tied in bundles about 1 meter in circumference, 
and carried to the place of use in carts or wagons The hills are cov- 
ered with the layers of heather described in the first part of this article 
(PL II, fig 1). 

The region consists of dunes more or less bare and shifting, alter- 
nating with lower moist areas where there is a covering of vegetation, 
mostty heather. These low areas are sufficientl}^ moist to keep the 
sand from drifting. Experience has shown that over much of this 
area trees do not thrive when set out in holes, as is customar}^ This 
seems to be due to the lack of air in the soil. It has therefore been 
found necessary to spade up the soil before the trees are planted. 
This is done by digging up the soil to a depth of 0.56 meter (about 22 
inches). It is unnecessary to spade up the soil over the entire surface, 
the digging being confined to strips 1.2 meters wide, with an unspaded 
space of 0.8 meter lying between. 

The trees are planted in rows, one near each margin of the spaded 
strip and 0.75 to 0.80 meter apart. Heather is laid between the rows 
to hold the sand. On the hills where the heather has ])een laid the 
trees may be planted in holes among the heather. The planting takes 
place in autumn or spring, but it is customar}^ to plant the hills in the 
fall, leaving the low places till spring, when it is drier (PI. II, fig. 1; 
PI. Ill, fig. 1). 

After the planting it is necessary to watch the growth of the trees 
and to stir the ground around them in proportion to their needs. If 
the growth is poor and the trees remain stunted the ground is stirred 
with a stout four-tined rake. If the soil is moved too much the trees 
may make too vigorous a growth and the wood will not ripen suffi- 
ciently in the fall. 

The tree best suited to the greater part of this region is the common 
pine or, as it is called in America, the Scotch pine {Pinus sylvedris). 
It was stated that the trees from Scottish seed grew better than those 
from Norway seed. 

On the more sterile portions of the area better results are olitained 
from Pinus rUjlda and /-*. divaricata Gord. i^P. hanksiana Lam.). 
The black or Austrian pine {Pinus austriacci) does not succeed well, 
its growth being too slow. Pinus laricio promises well. 

About one-fourth of 1 per cent of the trees die from various causes, 
and these it is necessar}^ to replace. Various insects prej^ upon the 
trees. In this connection it is noteworthy that bird houses are placed 
at intervals in the forest to attract birds that devour harmful insects 
or their larvae. A bird called the "birkhuhn" nips ofi' the ,young 
buds. Rabbits and other small animals gnaw the bark. A root fun- 
gus {Agaricus nielleus). kills many individuals. These are replaced by 
choke-cherry {Prunus virginiana). 



FIXATION IN DENMAKK. 25 

The cost of the work per hectare at this point is approximate!}" as 
follows: 

Guilders. 

Cutting and tying the heather 1.1 

Transporting the heather 1.5 

Spreading the heather 16 

Spading the ground 57 

Planting the trees 25 

This makes the total cost al)out 100 guilders per hectare, or about 
$16 per acre. 

The clilferent parts of the plantation are reached by means of roads 
■placed at convenient distances. There is usually a strip of deciduous 
trees, mostl}^ of birches, planted along these roads as a protection in 
case of tire, since conifers burn with ease, while the birches do not. In 
passing through the higher dunes, it is necessary to have the roads 
curve between them in order that the wind may not sweep through 
and cause serious erosion. 

DENMARK. 

Through the kindness of Prof. Eugene Warming, director of the 
botanical garden at Copenhagen, letters of introduction to the dune 
inspectors at Aar and Skagen were obtained. Dune areas extend all 
along the coast of western and northern Denmark, but these two 
points were selected as being typical of the entire region. 

♦ OXBOL. 

The first point visited was in the southwestern part of Denmark in 
the Province of Ribe. Mr. R. P. F. Bang, the inspector of this dis- 
trict, lives at Aar, near Oxbol, which is reached via Esbjerg and 
Varde. The method used here for fixing the sand and planting trees is 
similar to that used in Holland; the conditions are also very similar. 
The region consists of a series of sand dunes, with low places inter- 
spersed, and extends some distance back from the coast. There has 
been no attempt in this region to form a barrier dune. As the 
heather grows abundantly throughout most of the dune region this 
plant is used for the purpose of fixation except near the coast. The 
young forest consists for the most part of Plnus numtana and P'lcea 
alba. In addition, Mr. Bang has experimented with Plcea sitchensis 
and P. nordmanniana., both of which promise success. Plnus austriaca 
is injured by the cold winters, and Plcea excel sa does not successful!}^ 
withstand severe winds. On certain portions, where the soil is com- 
paratively rich, Plcea pectlnata succeeds. 

About fifty years ago an attempt was made to esta])!ish a forest in 
this region, and in certain isolated and protected places portions of 
this forest are now in evidence. The trees, according to the situation, 



26 METHODS USED FOR CONTEOLLING SAND DUNES. 

ma}^ be 3 to 15 feet hig-h, but for the most part present a ver}- stunted 
growth. 

The heather i.s laid at anj- time of the 3^ear when it can be most con- 
venienth' done." Near the coast, where beach grass is used, the plant- 
ing takes place as in Holland except that on account of the broken 
nature of the country and the strong winds it is found that the 
bunches of grass must be smaller, consisting onl}- of one or two 
pieces. The pines are planted when the}^ are 3 years old and the 
spruces at 4 years. The plantation showed a yery marked differ- 
ence in the condition of the trees, depending on the richness of the soil 
and the exposure. The stunting of the trees is yery noticeable in the 
natiye forest near the coast. The trees nearest the coast are small and 
scrubljy, and for some distance inland they bear yery few l)ranches on 
the windward side, therefore appearing yery lopsided. The entire 
cost of laying the heather, planting and raising the trees, is 300 crowns 
per hectare,'^ or about |3ii per acre. The usual compensation for 
planting the grass is about 8 cents per square rod, the work being done 
at a fixed price (4 ore) per 4 square meters. 



The inyestigation of the dunes around Skagen at the north end of 
Denmark was made in company with the inspector, ]\Ir. C. F. Dahlerup. 
The whole peninsula aboye Frederikshayn is one vast sand area con- 
sisting mostly of dunes. Between the dunes are more or less extended 
areas of flat land where the soil contains more humus. The^se lower 
portions can be used for grass and to a limited extent for other crops, 
but they must be fertilized and limed. For this purpose kainit and 
Thomas slag are used, and lupines are grown to supply nitrogen. The 
distance to the ground water determines the ayailabilit}- of the soil for 
crops, the most fayorable distance being about 18 inches. If the 
ground water lies lower than this the soil is too dry and if aboye this 
it is too wet for cultiyation. The land around Skagen and for about 
two miles south is owned priyately, but a large area south of this is 
owned by the Goyernment. The latter is carrying on a system of recla- 
mation upon this area, and also upon some of the land owned priyately. 
Upon the private land the cost is divided as follows: One-half is paid 
by the (Jeneral (xovernment, one-sixth by the province, one-sixth by 
the township, and one-sixth by the owner. 

The preliminary fixation is by means of beach grass planted in Octo- 
ber or November. Although in the more quiet portions of the dune 
the beach grass lives onl}'^ from five to ten j^ears, yet as it gradually 
dies out its place is taken b}^ various native plants which serve to 

"The methods used in planting^ have been deporibed in Tidskrift for Skoving, 12, 
Om de Nord-og vestjydyke Klitters Beplantning. 
^A crown equals 26.8 cents in American money. 



FIXATION IN GERMANY. 27 

hold the sand effectively. Heather also lasts about the same time, 
but the native plants tend to take its place as it disintegrates. One 
of the common plants found as a native covering is reindeer moss. 
Salic rejxms^ one of the willows, is an excellent plant for holding the 
sand, but thus far there has been no success in its artificial propaga- 
tion. On the large areas of beach-grass plantations the rows follow 
the contour lines and the planting extends from the base toward the 
apex of the hills, but the tops of the dunes are not planted. The cost 
of planting and gathering the grass is about the same here as around 
Oxbol. It is customary to hire one workman at a fixed price per 
square 3^ard, and this man provides the necessary helpers. 

The trees used here upon the plantation are mosth'^ Pinus montana 
and Picea alba. Plcea sltvhensis has been used to some extent and 
seems to do well, especially in wet places, but it has not yet been suffi- 
ciently tested. Plcea aiha withstands wind ])ut will not endure 
drought. The seed of the trees is planted in seed beds in May. The 
following spring, when the seedlings are one j^ear old, they are trans- 
planted to the nursery rows by an ingenious machine. It was said 
that by means of this machine 1,00<) plants could be transplanted at a 
cost of about 6 cents. The trees are finally set out upon the dunes 
when they are three years old. Besides the conifers mentioned, oak 
{Quet'cus sessUiflora) and Ijirch are emplojxd as tire guards. It is 
interesting to note that the heather comes in naturally in the birch 
plantations, but does not appear in the oak plantations. Alder is 
planted on low places for tiie purpose of enriching the land, the nod- 
ules upon the roots having the same function as those upon the roots 
of legumes. Mr. Dahlerup stated that there are in all about thirty- 
five plantations in Denmark along the west coast of Jutland, one of 
the largest being this one at Skagen. Concerning the interior plan- 
tations in the "heide" region, he said that the preliminary fixation is 
by )neansof heather, while the young forest is composed of Plmi-s mon- 
tana and Plcea excelsa. The latter is the best tree for the purpose, 
but it can not be grown successfully directh" upon the heather land. 
It is therefore necessar}^ to plant first Pin us montana.. This kills the 
heather and Plcea excelsa can be made to grow in the shade of the pine. 
Although Plnus ntontana can be successfully grown, it is inferior to 
Plcea excelsa so far as its usefulness for timber purposes is concerned. 

GERMANY. 

The most extensive work to be found in Europe in the reclamation 
of sand-dune areas has been done along the north coast of Germany. 
The coast of the North'Sea, and especially the North and East Friesian 
Islands, are continually subjected to the erosive action of wind and 
water, which requires not only extensive work in the protection and 
reclamation of dunes but much in the wav of mechanical obstruction. 



28 METHODS USED FOE CONTKOLLING SAND DUNES. 

The coast and harbors are protected in various ways by masonry and 
piles. Sand-dune works also extend in various places all along- the 
coast of the Baltic Sea, which, however, are fully described in Ger- 
hardt's book, previously mentioned. Therefore, for the purpose of 
inspecting the methods which are t3'pical of the whole coast, a visit 
was made to onl}^ one of the important sand-dune regions of Ger- 
many — the Kurische Nehrung- in northeastern Prussia. 

This is one of the most wonderful sand spits in the world, consist- 
ing of a narrow peninsula which extends northward from the region 
of Kranz for about 60 miles. To the west lies the open ocean of the 
Baltic Sea and to the east the bay called the Kurisches Hatf. The 
opening to the ba}^ lies just to the north of this sand spit. On the 
opposite shore is located the somewhat important town of Memel, 
and there are three or four towns or villages situated in various places 
along the peninsula. The strip of land is quite narrow, varying from 
1 to 5 miles in width. At one time this peninsula was covered with 
forests, but later the trees were removed and the region was soon 
converted into a series of shifting dunes. Besides the necessity for 
protecting the villages and arable land upon the peninsula it is neces- 
sary to prevent the increased encroachment of the sand upon the 
harbor to the east. For these reasons the Government undertook the 
reclamation of the whole peninsula. 

So much attention is given to this region in Gerhardt's work that 
it is unnecessary to do more than note a few points in which the 
methods differ from those used in the Netherlands and in Denmark. 
In the first place, a long barrier dune, the entire length of the peninsula 
on the \7est side, has been produced. This is kept in repair by means of 
beach grass and the necessar}^ sand fences. The beach grass is planted 
upon this dune in a much more exact and methodical manner than that 
seen elsewhere. The surface is first carefull}' laid ofi' with a line in 
squares called "quadrats,'" and the plants are placed with almost 
mathematical precision. The forest consists for the most part of 
Pin.KS montana. In the vicinity of Rossitten there are several large 
wandering dunes which have not been planted. These dunes are in- 
deed hills, being from 200 to 300 feet in height. As the general 
course of these shifting dunes is from the west toward the east, they 
will finally disappear in the waters of the Kurisches Hafi". For this 
reason it has l)een thought inexpedient to make plantations upon them 
except wdiere it has been necessary to protect villages and other val- 
uable propert3\ 

Through the kindness of Prof. Christian Luerssen, who gave a letter 
of introduction to the dune inspector of this region, the venerable Mr. 
Epha, a vetoi'an in the service of sand reclamation, every pains was 
taken to render the inspection of th(^ dunes easy and satisfactor}'. 
The success of the work in this region is impressive. The conditions 



FIXATION IN FRANCE. 



29 



are certainly as adverse as on any of the dune areas along the European 
coast; yet the vast sandy waste has been converted into a productive 
forest, which, with a comparatively small amount of attention, can be 
protected from further encroachment of the ocean. 

The cost of holding the sand by planting grass upon the wandering 
dunes of the Kurische Nehrung is said by Gerhardt to be from 170 to 
220 marks" per hectare, or $17 to $22 per acre. This includes gather- 
ing the grass, transporting it to the plantation, and the setting The 
gathering costs from 2 to 2.50 marks, while the transportation costs 
about 2 marks per 100 bundles for distances not exceeding 3 miles 
and about 3 marks where the distance is 3 to 5 miles. Planting is 
usually done by the day, the wages paid being 1.30 to 1.80 marks for 
men and from 1 to 1.20 marks for women. The laborers are mostly 
women (PI. VII, fig. 2). According to circumstances the cost of 
planting 100 bundles may be 3 to 8 marks. Where the grass to ))e 
used is obtained in the vicinity by thinning the dense bunches the 
total cost of planting may be 5 to 10 marks per 100 bundles. 

The cost of the brush fences, where this method is used, is about 0.20 
mark (5 cents) per running meter. This includes gathering the brush, 
preparing the stakes, and setting the fence. As the material is obtained 
from the waste brush in the neighborhood, no charge is estimated for 
this. The amount of material is at the rate of 0.05 cubic meter per 
running meter. At this rate one cord of the prepared brush is suffi- 
cient to set about 80 yards of fence. 

The cost of establishing a forest is given by Gerhardt as 1,200 marks 
per hectare ($120 per acre). This is the average of ten years' experi- 
ence upon the Kurische Nehrung and includes items as follows: 



Fixation of the shifting sand by means of sand or reed liedges 

Fertilizer 

Preparation of the holes for planting 

Planting the young trees, 400 to the hectare 

Miscellaneous expenses 

Total 



Cost per 
hectare. 



Marks. 
700 
300 
50 
125 
25 



1,200 



Cost per 
acre. 



Dollars. 
70.00 
30.00 

5.00 
12.50 

2.50 



120. 00 



FRANCE. 

The most important dune region in France is that along the south- 
western coast from the vicinity of Bordeaux to the Spanish line. 
Through the courtes}- of Mr. Poisson, a liotanist in the Jardin des 
Plantes, a letter of introduction to Mr. Emile Duregne, a civil engineer 
living in Bordeaux, who has been over the greater part of the dunes 



«A German mark is e(inal to 23.8 cents in American money. 



30 METHODS USED FOR CONTROLLING SAND DUNES. 

in his capacity as survej^or, was provided. Mr. Duregne is very- 
familiar with the whole region and with the methods which have been 
used to reclaim it, and has published some important papers upon the 
subject. The particular region visited was a few miles south of 
Arcachon. This is a part of the general dune system extending from 
the mouth of the Gironde River to Bayonne. Before this land was 
reclaimed a considerable portion lying back of the dunes was untit for 
agriculture, as it consisted of alternating sand hills and marshes. 
Since the reclamation the conditions have so changed that the popula- 
tion has very materially increased. A barrier dune, similar to the one 
found in the Kurischo Nehrung, extends all along the coast (PI. VI, 
fig. 1). This is held in place in the same manner; that is, by means of 
))each grass and brush fences. The most marked dilierence in the 
method of reclamation is in the fact that a forest was established by 
sowing the seed. The seed of Pinus maritlina is sown on the sand in 
October or November or in the spring during March and April, and 
the whole is then covered with brush or conifers. The seed soon 
germinates, and, protected temporarily by the brush, grows into a 
forest. 

The total cost of covering the area with forest, including the plant- 
ing of the trees and the covering of the land, is about 320 francs per 
hectare, or al)out $26 per acre. The grass for planting the barrier 
dune is dug up by means of a small mattock, and is set with a conical 
instrument having a horizontal handle. The grass is planted in rows 
parallel to the course of the dune. Breaches are repaired by means of 
sand fences (PI. IV, tig. 2), usually by placing two lines of fence 
about 6 meters apart and extending above the surface of the sand 60 
or 70 centimeters. As soon as these are covered a second line of fence 
is placed on top. The fence which was used in establishing the 
original barrier dune was placed a])Out 2 meters high. Where ravines 
are to be filled with sand it is common to use these fences in a net- 
work of squares. Some portions of this protecting dune reach the 
extraordinary height of 200 feet or even more. Theie is evidence to 
show that in former times some of these dunes had encroached upon 
the inland forest, killed the trees, and then passed over them, as stumps 
are to be found on the windward side along the shore (PI. V, fig. 2). 

Mr. J. Poisson" has described the method used upon the dunes of the 
Coubre, a peninsula which lies just north of the mouth of the river 
Gironde. The seed of Pinus marh'nna was sown at the rate of about 
5i pounds to the acre, mixed with one-half pound each of furze, 
broom, and beach grash' The total cost of covering 2,100 hectares 
was 766,142 francs, or jout $2i> per acre. 

« Sur la fixation des dunes dans I'ouest et dans le nord de la France. Extrait des 
Comptes Rendus de I'Association Fran(;aise jxHir 1' Avancement des Sciences. Paris, 
1900. 



FIXATION" IN FRAlSrCE. 31 

Mr. John Gifford, who has examined the dune region of the Landes, 
gives an account'^' of the methods used in the original work of recla- 
mation, which is here appended: 

A littoral dune was constructed straight along the shore from the mouth of the 
Gironde to Bayonne. This dune is the secret of all success in the fixation of shift- 
ing sand. It is simply a bank of sand of certain dimensions, with a certain slope 
suited to the condition of affairs. This protective, or littoral, dune is formed as fol- 
lows: A double fence is constructed of brush, or of imlisades driven in the sand. 
This stops the sand which comes from the ocean. Soon a ridge of sand forms, equal 
in height to the fence. A double fence is used, as it gives breadth to the dune and 
stops the sand which blows through the fence on the ocean side. As soon as a ridge 
of sand is formed as high as the fence, the old fence is pulled up or a new one built 
on top, and so on until a dune of the height desired is formed artificially. The 
proper height of a protective dune is 33 feet. It should slope 25 degrees toward the 
sea, and may be 60 degrees ^ on the land side. The dune must be at least 300 feet 
from high-water mark. After the dune has reached the proper size, it is kept in 
shape by the sea marram {Psamma arenaria).'^ This peculiar plant, called gourbet 
in France, is exclusively used for fixing the sand on the littoral dune. It has long, 
much-divided rhizomes, and will grow well only when covered with fresh sand. The 
dune must always be kept in shape. If sand accumulates in any one spot in undue 
amount, a draft is formed, which may end in a breach of the littoral dune. "Gardes 
cantonniers" are stationed along the dune to watch it closely, and here and there on 
this long, straight sand bank groups of men and women may be seen digging up the 
gourbet in places where it is too thick and planting it where needed. Constantly 
the dune is watched and mended; the forest, villages, and fields in its lee are depend- 
ent upon it, and it in turn is dependent upon the humble but persistent gourbet. 

After the formation of the littoral dune comes the work of planting in its lee. The 
surface of the sand is covered with brush arranged like the slates on a roof, with a 
shovelful of sand here and there to hold it down. Then the seeds of Pinus maritima 
are sown, with seeds of other plants to shade the young pines, and seeds to attract insec- 
tivorous birds. The pines usually come up well and grow quickly, although close to the 
littoral dune they are gnarled and stunted by the salt winds. Thus the sands are fixed, 
and, although the forests do not yield a good interest in cash, they are of incalculable 
value to a large proportion of the people of Gascony; in fact, indirectly, to the whole of 
France. Fire lanes have been constructed across the dunes, and, thanks to the watch- 
fulness of the guards and the rigid enforcement of laws, fires are almost impossible. 

Very little cutting is done in these forests, the revenue coming mainly from the 
resin industry. Owing to a lack of roads and insufficient means of transportation 
on these dunes, only the most valuable timber is marketed, after being tapped for 
resin. If it is desirable to remove a tree, it is bled to death before being cut. All 
other trees are tapped very carefully, and are in no way injured by the process. In 
fact, bled timber is considered superior to unbled in France. The Hague method of 
orcharding is used, a system which does not injure the tree, but gives a resin of bet- 
ter quality and more abundant turpentine. Another article, however, could be 
written on the French method of turi^entine orcharding. 

Other industries have started, the people have improved, and the country is more 
fruitful and beautiful, so that through the agency of trees a new province has been 
practically added to France. 

«The Control and Fixation of Shifting Sands. 1 the Engineering Magazine, 
January, 1898. 

b There is some error here in the angles given for the slope. The windward slope 
is from 4 degrees to 14 degrees, and the lee slope about 80 degrees. 

c Another name for beach grass {Ammophila arenaria). 

17170— No. 57—01- — -3 



32 METHODS USED FOR CONTROLLINCi SAND DUNES. 

SUMMARY. 

Extensive and systematic work is done by various governments in 
Europe for the purpose of reclaiming waste dune areas. The object 
ma}^ be to convert this waste into a productive forest, or to prevent 
the encroachment of the sand upon valuable property. 

The sand is first held in place b}^ some inert covering or a plantation 
of grass, and afterwards a forest is established by transplanting young 
trees. 

Trees will not grow in the immediate vicinity of the ocean; hence 
a narrow strip along the coast must be permanentl}" held in place by 
means of a sand-binding grass. 

The best grass for this purpose is beach grass {Amrnophila arenaria)^ 
which grows naturally along the sandy seashores of the North Atlantic 
coast. The same species grows along the shores of the Great Lakes 
and on the Atlantic coast of the United States as far south as North 
Carolina. 

The grass is transplanted in rows or squares in autumn or spring. 
Satisfactory results can not be produced by sowing the seed of this or 
of other plants directly upon the unprotected sand. 

Where heather grows in sufficient abundance this is cut and laid upon 
the surface of the sand. 

The third important method for preventing drifting is the use of sand 
fences. These consist of rows of rough stakes or pieces of brush driven 
into the sand and projecting above the surface from 1 to 3 feet. For 
holding the sand the shorter stakes are placed in squares of 9 to 12 feet, 
forming a network. For accumulating sand in hollows or repairing 
breaches in a protecting dune the high fences maj' be used. Solid 
fences are not used. 

The drifting of the sand having been prevented by one of the above 
methods, young trees are set out to form the permanent covering of 
forest. In northern Europe no satisfactor}" results have been obtained 
in establishing a forest by sowing the seed, but in southwestern Fmnce 
a forest was produced by sowing the seed of Ptnns maritima upon the 
sand and covering it with brush. 

The trees used are: In the Netherlands, Pmus austriaca and P. laricio 
near the coast, P. xylvestris on the interior dunes; Denmark, Piinis 
montana near the coast and Picea excelsa (preceded by Pinustnontana) 
on interior heath land; Germany, Pinus montana; France, Pinus 
inaiitlma. 

On the Kurische Nehrung and in other parts of Prussia, and in 
Gascony, a long barrier dune has been formed artificially to protect 
the land lying back of it. This is kept in repair bv planting beach 
grass and b}' the use of sand fences when necessary. 



PLATES. 



33 



DESCRIPTION OF PLATES. 

Plate I. frontispiece. Beach grass {Ammuphila arenarin Link). Drawing from her- 
barium specimen. 

Plate II. Fig. 1. — Inland dunes near Barneveld, the Netherlands. In the background 
the dunes have been covered with heather to prevent drifting and afterwards set 
out with Pinus sylvestris. In the foreground the pines have been planted without 
a covering of heather, as the sand is here moist enough to prevent its drifting. 
Fig. 2. — Inland dunes near Barneveld, the Netherlands, showing road in process 
of construction through the plantations. In the background the dunes are 
covered with heather. In the foreground is the road, the sand being ridged up 
with ditches at each side. Upon the sand is placed heather in a thick layer. 
This prevents the wheels of vehicles from sinking into the loose sand. 

Plate III. Fig. 1. — Inland dunes near Barneveld, the Netherlands, showing a plan- 
tation of Pinus sylvestris on a covering of heather. The sand is first covered with 
a layer of cut heather to prevent its drifting. Fig. 2. — Unreclaimed sand dunes 
near Alkmaar, the Netherlands. In the foreground is a low area partially 
covered with heather. In the interior such areas furnish the heather, which is 
cut and laid upon the surface of the sand to prevent its drifting. 

Plate IV. Fig. 1. — Plantation of beach grass upon the dunes near Oxbol, Denmark. 
This shows how the plantations are made along the lower places and part way 
up the slopes of the dunes, the tops remaining unplanted. The grass will be 
planted somewhat higher on the slopes as opi^ortunity permits, but the tops will 
be denuded of grass to facilitate the removal of the sand by the wind. Fig. 2. — 
Barrier or protecting dune south of Arcachon, France. To the left beach grass 
has been planted in rows j^arallel to the beach. In the center is a sand fence, 
placed to repair a breach, which is now nearly covered with sand. To the 
extreme right is the forest in the lee of the dune. 

Plate V. Fig. 1. — Lee slope of a portion of the barrier dune south of Arcachon, 
France. Since the dune has been fixed on the windward slope, the advance of 
the sand inland has been very slow, as shown by young trees growing along the 
slope. Fig. 2. — Unreclaimed sand dunes south of Arcachon, France. The 
stumps are the remains of a forest which has been covered and again uncovered 
by an advancing dune. 

Plate VI. Fig 1. — General view of the barrier dune south of Arcachon, France. 
This dune stretches along the coast from Arcachon to Bayonne, about 75 miles, 
and protects the forest of Pinus maritvma in its lee at the right. The ocean is 
seen at the left. This dune was formed artificially with the help of sand fences 
and beach grass and is now held in position by the same means. [From a pho- 
tograph by Mr. E. Duregne.] Fig. 2. — Unreclaimed sand dunes south of Arca- 
chon, France. The sand is drifting badly at this point. Here and there a snail 
hillock is held in place by a bunch of beach grass. 

Plate VII. Fig. 1. — Laborers digging beach grass near Alkmaar, in the Netherlands. 
The instrument used for this purpose here is a spade with a rounded point. The 
grass is obtained upon the dunes where it is growing naturally, by thinning out 
the bunches. In the background may be seen the unreclaimed dunes partially 
covered with vegetation. Fig. 2. — Laborers setting out beach grass upon the barrier 

35 



86 METHODS USED FOK CONTROLLING SAND DUNES. 

dune at Rossitten, on the Kurisehe Nehrung. At the right is the overseer. The 
grass is set in squares or ' ' quadrats. ' ' The position of the rows is determined quite 
accurately by stretching a line between two poles, one of which appears in the 
illustration. One laborer makes the holes with a planting spade, while another 
sets the grass. At the left may be seen a bundle of the grass ready to be set. 

Plate VIII. Fig. 1. — Protecting the base of a barrier dune by means of two rows of 
sand fences. Storms had eaten away the fa,ce of the dune and the fences are 
placed to accumulate sand, after which grass will be planted. [From a cut in 
Gerhardt's Diinenbau.] Fig. 2. — Protecting a road through the dunes, on the 
Frische Nehrung, Prussia. The road is curved and the slope is held by cover- 
ing with a layer of reeds and placing poles upon these. [From a cut in Gerhardt's 
Diinenbau.] 

Plate IX. Fig. 1. — Shifting dunes held by sand fences on the Kurisehe Nehrung, 
Prussia. The fences are of brush placed in squares. Nearer the strand the 
brush is in rows parallel to the beach. [From a cut in Gerhardt's Diinenbau. J 
Fig. 2. — Shifting dunes held by means of sand fences of reeds, on the Kurisehe 
Nebrung, Prussia. Next to the strand the reeds are placed in rows parallel to 
the beach. Farther up on the dunes they are placed in squares. A roadway 
passes through at this point. [From a cut in Gerhardt's Diinenbau.] 



o 



Bui. 57, Bureau of Plant Industry, U. 5. Dept. of Agriculture, 



Plate II. 




Fig. 1.— Dunes Held by Covering of Heather. 




Fig. 2.— Making a Road in the Dunes. 



Bui. 57, Bureau of Plant Industiy, U. S. Dept. of Agriculture. 



PLAT£ III. 




Fig. 1.— Pine Plantations in Covering of Heather. 




Fig. 2.— Heather Among the Dunes. 



Bui. 57, Bureau of Plant Industry, U. S. Dept. of Agriculture. 



Plate IV. 




Fig 1.— Beach Grass Plantation Along Base of Dunes. 




FiQ. 2.— Beach Grass and Sand Fence on Barrier Dune. 



Bui. 57, Bureau of Plant Industry. U. S, Dept. of Agriculture. 



Plate V. 




Fig. 1.— Lee Slope of Barrier Dune. 




Fig. 2.— Remains of Once Buried Forest. 



Bui. 57, Bureau of Plant Industry, U. S. Dept. of Agriculture. 



Plate VI, 




Fig. 1.— General View of Barrier Dune. 




Fig. 2.— Unreclaimed Shifting Dune. 



Bui. 57, Bureau of Plant industry, U. S. Dept. of Agriculture. 



Plate VII. 




Fig. 1 .—Digging Beach Grass for Planting. 




Fig. 2.— Transplanting Beach Grass. 



Bui. 57, Bureau of Plant Industry, U. S. Dept, of Agriculture. 



Plate VIII. 




Fig. 1.— Sand Fences Protecting Base of Dune. 





1 




1 






m 






:^ 


-J: 

■tm 


1 




P 


... ■ ■■ ' ■ ^' ' ■ * 


''' - 1 



Fig. 2.— Protecting a Road Through the Dunes. 



Bui. 57, Bureau of Plant Industry, U. S. Dept. of Agriculture. 



Plate IX. 




Fig. 1.— Shifting Dunes Held by Brush Fences. 




t^-^iJi'tt.j^ tAi «..tt,uKiUMi£iiiiiiMiittiJku«iiMhitteMiM^^^ ..^^: — 



Fig. 2.— Shifting Dune Held by Reed Fences. 



LEMr'OP 



J 



